The prior art appears to be best exemplified by the following U.S. Pat. Nos.:
______________________________________ Redmond 3,986,640 10/76 Lowry 3,315,801 4/67 Lowry 3,355,854 12/67 Hellstrom 3,472,368 10/69 Hellstrom 3,472,367 10/69 Marks 3,759,371 9/73 Hoag 2,499,313 2/50 Hoag 3,263,863 8/66 Becker 3,223,310 12/65 Sparks 3,207,299 9/65 Hellstrom 3,689,458 9/72 ______________________________________
This invention relates to improvements in packages for dispensing flowable products, e.g. cream, jelly, shampoo, talc, etc. in a desired quantity.
Various proposals exist in the art for the packaging of flowable products in the quantity in which such product will be normally used. A ready illustration is the now familiar package made from sheets of relatively thin plastic, sometimes laminated with other plastics or with foil, commonly used to dispense ketchup, mustard, etc. In order to open such a package, the sheets must be ripped through the sealed edge and across the envelope in which the flowable material is contained. It commonly happens that the package is difficult to open or rips uncontrollably squeezing product out during opening.
In U.S. Pat. No. 3,986,640 to Redmond, there is described a package which is formed by superimposing a sheet of relatively flexible material over a sheet of relatively stiff but flexible material with the product to be packaged between the sheets. The relatively stiff material, forming one of the faces of the package, is cut through in a pattern and the cut pattern thereafter is coated or covered with a sealant such as a plastic coating, wax or foil to prevent seepage. The package opens by bending or folding the container at the cut pattern since as the package is folded back, the cut stiff material ruptures the sealant at the cut and the edges of the cut open up allowing the product to flow out of the package. Such a package as described therein represents a considerable improvement over prior art packages. However, neither the sealant applied over the cut nor the relatively stiff material of the package impart barrier protection to the contents of such a package. As a result, products contained in such packages lose moisture and may become dehydrated when stored for extended periods, e.g. within six months.
The present invention provides an improvement in such and similar packages as disclosed in the Redmond patent.
The packages of the present invention have improved package strength, have moisture barrier properties and afford protection of the packaged product from contaminants through the utilization of an imperforate, uniaxially oriented polymeric plastic sheet layer which is attached over the scored, relatively stiff (rigid or semi-rigid) member. The imperforate film is unimpaired in its barrier properties and is oriented to the extent that it exhibits a differential in tear strength which makes it easily ruptured to form an opening through which product can flow upon bending the package. The protective film layer ruptures without the exertion of a tearing action or other physical weakening or exertion of pressure, the forces generated during bending of the package being sufficient to initiate the rupture of the score and of the superimposed uniaxially oriented film.
The package of the instant invention may be formed by the general method disclosed in U.S. Pat. No. 3,986,640. Briefly, the package is formed by superimposing a web or sheet of relatively flexible material over a cut through or scored web or card of rigid or semi-rigid material after which a layer of imperforate, uniaxially oriented polymeric film is superimposed over the scored rigid material. The product to be packaged is placed between the sheets and the sheets are joined to each other at their respective marginal edge portions, for example, by heat sealing. Alternatively, the package may be filled, sealed and scored and the imperforate oriented film may then be attached to the scored member, either adhesively or by heat sealing or the imperforate oriented film may be attached to the scored rigid member and shipped, together with the flexible member for filling and sealing by the product manufacturer. Wax, foil or plastic coating sealants are not necessary since the final oriented film functions to fill the cut area as well as to provide package strength, moisture barrier properties and protection from contaminants to the entire surface of this face of the package.
To remove or dispense the product, the package is bent or folded away from the scored area toward the pocket. The flexible material sides of the package at the opposite sides of the scored area are folded to contact each other. As the package is folded or bent, the scored material, as well as the imperforate oriented film superimposed thereover, is ruptured; the edges of the scored area and the imperforate film open up allowing the product to flow out. By pressing the flexible sides against each other or by folding the package upwardly in a V, the product can be squeezed out of and discharged from the package.